I limit my list to the top five. In no particular order:
Juan Rangel - It's a shame that more people on the forum today haven't had a chance to see him play, I think he would've been near the top of more people's lists. Super flowey and super smooth, I think he did torques better than anyone else. Also, aside from shred-style, he has one of the best personality-style's around, and is definitely one of my favorite freestyler's to hang out with.
James Risden - It's easy to see that Peter Irish was his favorite shredder. Actually, I would have included Peter on this list too but I didn't feel right to have them both and I think James has a slightly better and smoother Peter-style than Peter does

. Sorry for the blasphemy
Jim Penske - All his string look just savage. I love his huge rubbery dexes too, he must have extra cartilage in his joints or something. Style-wise he's my favorite active shredder.
Lon Smith - Lon
plays footbag better than anyone else. I enjoy watching Lon do alternating toe kicks more than I do watching most people actually freestyle.
Brian Makenzie - Might have been my original favorite style. I think in most cases high ankle crank will lead to an interesting style, and Brian had some of the best crank ever. I remember just being in awe of his zoom sets (out of blender and torque tricks which back in 99 was pretty huge) and the cool little pause he did after the osis but before the spin. He was also the first person I ever saw hit Marius and I remember being convinced at the time that he was the only person in the world with the ankles possible of hitting such a hein trick

.
Also, I'm going to agree with Cod (though not with as much style or flavor) that while I love watching Vasek and Jorden (and I'm going to include DC here too) play, their styles are so textbook and flawless that they lack character to me. Just my opinion, I still look forward to any videos they put out.